Hyperperfusion in middle-aged individuals with genetic risk of sporadic Alzheimer’s disease

Extensive brain hypoperfusion is well-established in people with Alzheimer’s disease (AD). However, mixed findings have emerged during the pre-symptomatic disease stage. In this study, we used arterial spin labelling (ASL) MRI in middle-aged, cognitively normal participants from the PREVENT-Dementia study to evaluate cerebral perfusion differences between carriers and non-carriers of the apolipoprotein ε4 (APOE4) allele. The ASL spatial coefficient of variation (CoV) was used as a proxy for arterial transit time (ATT) delays. We found hyperperfusion in APOE4 carriers which was not accompanied by increased spatial CoV, suggesting that the observed hyperperfusion is not driven by ATT delays.